Due to their chemical nature, polyethers are inherently hydrophilic and are a well-recognized class of materials, especially for dental applications. Polyether-containing compositions and their use in the dental field are also subject of several patent applications.
US 2004/0014924 A1 relates to silicone based aziridino compounds. The materials described show functionality of at least two aziridino groups in the average molecule having a prepolymeric structure. The general formula shows structures with aziridino functions pendant from a silicone backbone.
US 2004/0014907 A1 describes linear and branched prepolymeric silicones bearing terminal and/or pendant aziridino moieties and curable compositions made thereof.
WO 2004/014323 A1 relates to monofunctional aziridine compounds which can be used to enhance speed of cure. The addition of monofunctional aziridine compounds to a given concentration of aziridine compounds with at least two aziridine rings enhances speed of cure.
Other publications that mention the use of aziridines are WO 92/19655 A1, U.S. Pat. No. 5,164,467 A1 and U.S. Pat. No. 4,605,698 A1.
So far achieving a sufficient tear strength value of the compositions described has not been an issue. Some of the compositions, however, might lack sufficient tear strength bearing the risk of rupture of thin parts of material when the set impression is removed from the mouth or a plaster model is removed from the impression.
Thus, there is a need for a polyether containing composition having improved properties, especially with regard to tear strength.